C#调用 C++写的DLL传递结构体的问题

[shuihan20e]

C++结构体声明如下

struct CTollRate
{
	DWORD BaseWeightTollRate;	//spare1
	DOUBLE FavRate1;			//spare7
	DOUBLE FavRate2;			//spare8
	DWORD PunishRate1;			//spare2
	DWORD PunishRate2;			//spare3
	double LegalOverFav;				//spare6
};

struct CMoneyByWeight 
{
	DOUBLE BaseMoney;
	DOUBLE OverMoney1;
	DOUBLE OverMoney2;
};

接口如下

FARE_CALL_DLL_API DOUBLE WINAPI CalWeightMoney(DWORD dwAxis, DWORD dwTotalWeight, DWORD Meters, const CTollRate &TollRate, CMoneyByWeight *pMoneyByWeight)

翻译成C#代码如下

        [StructLayout(LayoutKind.Sequential,CharSet = CharSet.Ansi, Pack = 1)]
        public struct CMoneyByWeight
        {
            public double BaseMoney;
            public double OverMoney1;
            public double OverMoney2;
        }

        [StructLayout(LayoutKind.Sequential,CharSet = CharSet.Ansi, Pack = 1)]
        public struct CTollRate
        {
            public UInt32 BaseWeightTollRate;
            public double FavRate1;
            public double FavRate2;
            public UInt32 PunishRate1;
            public UInt32 PunishRate2;
            public double Spare;
        }

接口如下

        [DllImport("FareCalcDll.DLL", EntryPoint = "CalWeightMoney", CharSet = CharSet.Ansi, CallingConvention = CallingConvention.StdCall)]
        public static extern double CalWeightMoney(UInt32 dwAxis, UInt32 dwTotalWeight, UInt32 Meters, CTollRate TollRate,ref CMoneyByWeight pMoneyByWeight);

调用代码如下

CMoneyByWeight cmoney = new CMoneyByWeight();

CTollRate rate = new CTollRate();
rate.BaseWeightTollRate = 8;
rate.FavRate1 = 6.0;
rate.FavRate2 = 3.0;
rate.PunishRate1 = 2;
rate.PunishRate2 = 4;
rate.Spare = 0;

double money = 0.0;
money=CalWeightMoney(2, 10000, 10000, rate, ref cmoney);

运行时总是提示“未AccessViolationException 尝试读取或写入受的内存。这通常指示其他内存已损坏
期待高手帮忙，急

[Poopaye]

CTollRate TollRate ---> ref CTollRate TollRate

[马少华]

        [DllImport("FareCalcDll.DLL", EntryPoint = "CalWeightMoney", CharSet = CharSet.Ansi, CallingConvention = CallingConvention.StdCall)]
        public static extern double CalWeightMoney(UInt32 dwAxis, UInt32 dwTotalWeight, UInt32 Meters, CTollRate TollRate,IntPtr pMoneyByWeight);

 CMoneyByWeight t = (CMoneyByWeight)Marshal.PtrToStructure(pMoneyByWeight, typeof(CMoneyByWeight));